Thanks for your bugreport. Could you please attach the file /var/lib/apt/lists/extras.ubuntu.com_ubuntu_dists_trusty_InRelease ?
** Changed in: apt (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1309236 Title: E: GPG error: http://extras.ubuntu.com trusty InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1309236/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs